Press



July 1&8, 1944. H. F; MacrvnLLm ETAAI.

PRESS Filed Jan. 16, 1941 Haw/mn F. MMMILLIN,

JOHAN Affre Clt/Ways,

Patented July 148, 1944 UNITED STAT-ES APATENT OFFICE PRESS Application January 16, 1941, Serial No. 374,7l3

2 Claims.

This invention relates to presses, and vin particular to press bodies having a cylinder with a reciprocable pressing plunger therein.

Heretofore, press bodies having a press cylinder had the press body and press cylinder cast as an integral unit so that the press could be used with a pressing plunger of a definite diameter only. Consequently, if with such a press work pieces were to be shaped which require only a pressure materially less than that obtainable by said pressing plunger, the press works highly uneconomically, not only because a great amount of energy is Wasted but also. because, in case a hydraulic press is used, the press Works too slowly due to the time required for filling the large press cylinder. On the other hand, with the presses heretofore known it is not possible to exert a higher pressure than that which corresponds to the diameter of the pressing plunger pertaining to said press.

Accordingly, it is an object of the invention to provide a press body which will remedy the above mentioned drawbacks and will make it; possible to use one and the same press body with a variety of pressing plungers of different diameters.

It is another object of the invention to provide a press body of the character referred to in the preceding paragraph, in which the press cylinder has uid inlet and outlet means and is, together with said means, exchangeably mounted lin the press body.

A lfurther object of the invention consists in the provision of a press body having a hydraulically operable press cylinder-piston-assembly, in which the press cylinder may be replaced by a press cylinder of a different inner diameter, without affecting the fluid inlet and outlet means associated with the press body.

It is a still further object of the invention to provide a press body for a hydraulic press, in which the press cylinder has connected therewith fluid inlet and outlet means and may, together with said fluid inlet and outlet means, be replaced by another cylinder of a different inner diameter without changing the press body proper.

These and other objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawing, in which:

Figure 1 shows an embodiment of the invention in connection with a pressing plunger of relatively small diameter.

Figure 2 is a section along the line 2-2 of Figure 1, but with a slightly different sized press cylinder and plunger therein.

General arrangement According to the present invention the press body has a press cylinder which, in contrast to the conventional designs, is not integral with the press body but is inserted therein and may be exchanged with press cylinders having the same outer diameter butl a different inner diameter for receiving a different sized press plunger.

According to one embodiment of the invention the insertable press cylinder has connected thereto fluid inlet and outlet mean-s so that removal of the exchangeable press cylinders will simultaneously remove the fluid inlet and outlet means.

Structural arrangement Referring first to Figure l, the press body shown therein comprises a press head I 0 and a press bed II connected with each other by side elements IDU having strain rods I2 and nuts I3. The side elements each have guiding apertures or slots IDI into which slidably t the flanges |02 of the platen 3|.

Provided in the press head IIi is a bore I4 in which is exchangeably mounted a press cylinder I5. The press cylinder I5 may be connected with the press head I0 in any convenient manner, for instance by screws I6 and, to this end, is prefer ably provided with a flange Il. The upper portion of the press cylinder I5 has a chamber I8 into which extends a surge valve I9 connected in any convenient manner with the press cylinder body l5. The surge valve I9 is provided with a baie plate 20 to prevent the fluid escaping from the press cylinder through the surge valve from splashing to the top and side walls of the fluid storage or surge tank 2l mounted on top of the press head I0.

Reciprocably mounted in the press cylinder body I5 is a press piston 22 with an advancing area 23 and a retraction area 24 which latter is formed by the difference in diameter of the press piston 22 and the piston shaft 25 connected to the piston 22.

To prevent leakage between the press cylinder I5 andthe piston shaft 25, packing material 26 compressed by a gland 21 is provided at the lower end of the press cylinder body I 5. The lower end lof the piston shaft 25 is connected in any convenient manner, for instance by connecting discs 28 and 29 and screws 30, with a platen 3| which may be guided by gibs or any other convenient means in the usual manner in the press body.

The press platen 3| is provided with bores 32 through which pass rods 33 having their lower ends connected with a yoke 34 carrying an ejector 35. The rods 33 are guided in eyes 36 and 31 and may be provided with collars 38 and 39, or with cams in the conventional manner for controlling any mechanism associated with the press. The rods 33 are suspended in the platen 3| by means of nuts 33a.

The upper and lower ends of the press cylinder body communicate with conduits for alternately admitting and exhausting uid to and from the press cylinder.

Provided in the press head I0 is furthermore a channel 42 communicating with the surge tank 2| and adapted to be connected with conduit means for admitting iluid to or withdrawing fluid from said surge tank. 44 is a bolster plate in the press bed for receiving the lower die or the work piece.

The press operates in the usual manner. When uid is withdrawn through conduit 4|, the press piston 22 with the piston shaft 25 moves downwardly by gravity, while the 'surge valve I9 admits uid from the surge tank 2| to the space above the piston 22. Simultaneously, fluid is introduced from a fluid source through conduit 40 into the space above the piston 22.

When the press platen 3| engages a work piece, pressure builds up in the space above the piston 22 so that the surge Valve I9 closes. The surge valve I9 do-es not form a part of the present invention and for a more detailed description thereof reference may be had to the U. S. Patent No. 2,193,248, issued March 12, 1940, to Walter Ernst. When the pressing stroke is completed, fluid is withdrawn from conduit 40 and admitted to the retraction area 24 through conduit 4| so that the piston 22 with piston shaft 25 and platen 3| moves upwardly. When the platen 3|, during its retraction stroke has reached a predetermined point of travel the ejector 35, by means of the rods 33 and yoke 34, will have been lifted to such an extent that it has passed the bolster plate 44 and ejected the work piece.

The press consists of two sub-assemblies which may be assembled according to the desired tonnage at the factory. The first sub-assembly consists of a press bed side elements |00, strain rods or other fastening means and press platen l0. These are assembled with the flanges |02 of the platen in proper position in the slots or apertures IGI. The other sub-assembly consists of the press head I0 having a standard inside bore, the cylinder body 45 having a standard outside diameter substantially the same as the inside diameter of the press head so as to t within the standard inside diameter of the presshead, and having an internal bore and a piston 22 Iitting therein.

In order to con-struct a press of the desired tonnage, the elements constituting the rst assembly are assembled together, the elements being of the proper dimensions. The elements forming the second sub-assembly vary as to the cylinder and piston, i. e., a cylinder and its corresponding piston are selected having the proper diametered piston and cylinder bore, which will provide a press of the desired tonnage, and these are assembled with the standard press head I0 and the flange by screws I6 as heretofore stated, to make up the second sub-assembly. This second sub-assembly is connected to the first sub-assembly by placing the press head with its previously assembled cylinder and piston onto the side elements. The fastening means, such as the strain rods |2 and nuts I3 are connected to the press head and the platen connected to the i end of the piston by screws 30 in any order desired.

The surge tank 2| and surge valve I9 with baffle plate 20 may be assembled at any time, either during the assembly of the second described sub-assembly or after the rst and second sub-assemblies have been connected to each other.

Each sub-assembly is separately made up and they are then connected together as stated, preferably at the factory.

B-y providing the press heads Il, 5| with a plurality of exchangeable cylinder bodies |5 and 45, only one single press body is required for economically performing a plurality of different pressing operations which require different power and which heretofore could be economically carried out only with a plurality of complete presses.

I1; will be understood that we desire to comprehend within our invention such modifications las come within the scope of the claims and the invention.

Having thus fully described our invention what we claim as new and desire to secure by Letters Patent, is:

1. A press comprising a bed, said bed having spaced side elements extending vertically from said bed, a press platen slidably mounted between the side elements, said bed, side elements and press platen constituting a sub-assembly; a press head having a main bore therein constructed to a standard inner diameter, a cylinder body having an internal bore and a standard external diameter substantially the same as the inner diameter c-f said press head, said body being disposed within the bore of said press head, means for detachably connecting said cylinder to said head, a piston located within said internal bore of said cylinder body and provided with a piston rod, said piston rod being provided with means for detachable connection with said press platen; said press head, cylinder body, piston and piston rod constituting an additional sub-assembly; said second named sub-assembly being disposed on top of said first named sub-assembly, means attaching said side elements to said base and said press head to said side elements; whereby in the assembly of said second named sub-assembly one of several cylinders of differently sized internal diameter but of the same external diameter and a piston to t said cylindenbore may be positioned within the bore of said press head, thereby to effect a press of desired tonnage, said side members further having means for guiding said platen and positioning the same relative vto said piston to facilitate alignment of the platen and piston during the assembly of said rst named assembly and said second named assembly.

2. A press comprising a bed, said bed having spaced side elements extending vertically from said bed, a press platen slidably mounted between the side elements, said bed, side elements and press platen constituting a sub-assembly; a press head having a main bore therein constructed to a standard inner diameter, a cylinder body having an internal bore and a standard external diameter substantially the same as the inner diameter of said press head, said body being disposed within the bore of said press head, means detachably connecting said cylinder to said head, a piston located within said internal bore of said cylinder body an d provided with a piston rod, said pistonrod being provided with means for `detachable connection with said press platen; said press head, cylinder body, piston and piston rod constituting an additional sub-assembly;

side members further having means for guiding said platen and positioning the same relative to said piston to facilitate alignment' of the platen and piston during the assembly of said first named assembly and second namedassembly, said attaching means including a plurality of strain rods having fastening means at each end thereof for engaging said base and press Head.

HOWARD F. MACMILLIN. JOHAN A. MULLER.. 

